Looper mechanism for sewing-machines.



Patented Nov. 27, I900.

A. SPEAB. LOOPEB MECHANISM FOR SEWENG MACHINES.

(Application filed Oct. 16, 1899.)

(No Model.)

IIIIIIIIIIIIIIIIIIIIIIIIHIIIMII 'II/IIIIIIII/IIIIIIIII dramas ATENTFFIQEl ARTHUR SPEAR, OF ornoneo, ILLINOIS, ASSIGNOR TO E..L. GILFILLAN,or SAME PLACE.

LOPER MECHANISM FOR SEWlNG ll/lACHlNES.

SPECIFICATION forming part of Letters Patent No. 662,832, dated November27, 1900. Application filed October 16, 1899. serial No. 783,738 (Nomodel.)

To (all whom 221; may concern:

Be it known that I, ARTHUR SPEAK, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Sewing-Machines, ofwhich the following is a full, clear, and exact specification. Y

My invention relates more particularly to sewing-machines in which thereis usually employed a hook or some other form of looper which passesthrough the loop as it is cast out by the needle and forms the stitch,and of this class of machines my invention has more especial referenceto that species in which both the needleloar and the hook-shaft orlooper are given the desired movements from a single crank-shaft. Inmachines of this character it has been difficult to form the loop orstitch in such a manner as to prevent puck ering of the goods, but moreespecially to produce an open or loose chain-stitch which will becapable of considerable stretch, so as to be suitable for elastic goodsof which under wear and other garments are made, and this difficulty hasbeen due mainly to the fact that the hook or looper lets go the loop toosoon with reference to the upward movement of the needle, therebypermitting the needle to pull the thread against the under side of thegoods, and thus produce the objectionable tight stitch.

The primary objectof my invention, therefore, is to provide an improvedmovement for sewing-machines of the described character which willproduce a fast and slow rotation to the hook or looper, so that it maybe caused to pass through the loop with the requisite rapidity, but todwell in its rapid movement just before the needle reaches the end ofits upward movement, so as to retain the loop until the needle and feedhave about finished their pull on the thread.

With these ends in view my invention consists in certain features ofnovelty in the construction, combination, and arrangement of parts bywhich the said objects and certain other objects hereinafter appearingare attained, all as fully described with reference to the accompanyingdrawings and more particularly pointed out in the claims.

In the said drawings, Figure 1 is a vertical longitudinal sectional viewof a sewing-machine head provided with myimprovements. Fig. 2 is atransverse sectional view taken on the line 2 2, Fig. 1. Fig. 3 is aperspective View of the crank which operates the looper-- shaft, andFig. 4 is adetail view illustrating the irregular curvilinear travel ofthe lower end of the longitudinally and transversely moving lever.

1 represents the needle-bar, which has operative connection in anysuitable way to a pivoted lever 2, and 3 represents the hook or loopershaft, which is connected in the usual or any suitable manner to thehook or looper t. The lever 2 is oscillatedin a vertical plane and theshaft 3 rotated by a common crank 5, secured to a suitable crank-shaft6, mounted in the head 7 of the machine at a point consid- 7o erablyabove the base 8 and having a wheel 9, whereby the machine may beoperated by either hand or foot power. The crank 5 carries a wrist orcrank pin 10, which is journaled in a vertical lever 11 at about themid-length of the latter and which imparts to said lever both arising-and-falling or longitudinal and a transverse or oscillatorymovement. The upper end of this lever 11 is connected to the end of thelever 2 by a ball-andsocket shaft 12 or any other suitable connection,thus permitting the upper end of the lever 11 to rise and fall with thecrank 5 and impart the desired vertical oscillation to the needle-bar1ever 2, while at the same time serving a fulcrurn for the lever 11 andcausing its lower end to oscillate or vibrate from side to side as thecrank 5 revolves. The lower end of the lever ll is provided with a stud13, which fits into a slot or way formed on a crank 14, se- 0, cured tothe shaft 3 by set-screw 15 or other suitable device, whereby the crank14 may be set or timed with reference to the movement of the hook 4c andthe needle-bar. The slot or way in the crank 14: may be formed in anysuitable manner. In the accompanying drawings I have shown the face ofthe crank 1a as provided with two parallel flanges 14, which constitutea way or slot 16. By this means it will be seen that as the crank 5revolves the lever 11 will be vibrated both longitudi nally andtransversely, and this transverse movement will impart a rotary movementto the shaft 3, and by virtue of this combination of movements the stud13 will be carried in the curvilinear orbit 17, (shown in dotted linesin Fig. 4,) composed of a complex curve less convex on its upper sidethan on its lower side and abruptly curved at its ends, and as aconsequence the hook 4 will dwell or slow up at two points duringasinglerotation, such points being Where the stud 13 passes around the abruptcurves, for at such points the stud 13 is necessarily farthest from thecenter of the shaft 3. The parts may be so timed and adjusted that theslow movement of the hook 4 will occur just shortly before it casts offthe loop, thus preventing the thread being drawn taut against the underside of the fabric. It will also be seen that by the described meansIproduce a simple, eflicient, and inexpensive sewing-machine capable ofhaving the bands heel located away from the base and also below theneedle-bar lever 2, which latter in consequence may be a simpleoscillating lever.

Having thus described my invention, What I claim as new therein, anddesire to secure by Letters Patent, is

1. In a sewing-machine the combination of a needle-bar, a lever foroperating said bar, a lever connected at one end to said first lever, alooper or hook, a shaft for operating said hook or looper, a slottedcrank on said shaft a stud on the other end of said second leverengaging in said slot for imparting a fast and slow rotation to saidshaft, and an operating-crank having a wrist-pin engaging said secondlever at a point between its points of connection with said first leverand slotted .nected with said lever at an intermediate point,substantially as set forth.

3. In a sewing-machine the combination of a needle-bar, a looper-shaft,a pivoted lever operatively connected to said needle-bar, a verticallever having its upper end jointed to said pivoted lever and suchjointed end being confined to an upright rectilinear move ment and itslower end provided with sliding crank connection with said looper-shaft,and an operating-crank connected With said vertical lever at anintermediate point, substantially as set forth.

ARTHUR SPEAR. \Vitnesses:

EDNA B. JOHNSON, F. A. HOPKINS.

